Good Science: How Organochlorines Are Making Us Fat

You've dieted. You've lost 20, 30, 100 lbs. It all came back as soon as you stopped starving yourself.

Perhaps you blamed yourself for weak will. Perhaps you thought being fat was "in your genes." But there's a new possibility revealed in research that was published without any fanfare 5 years ago.

Perhaps you are being poisoned by the plastics, pesticides and industrial solvents that have contaminated our air and water and which are now being found in the blood streams of 60% of Americans.

Here's the study:

Thermogenesis and weight loss in obese individuals: a primary association with organochlorine pollution. A Tremblay1 et al. International Journal of Obesity (2004) 28, 936–939. doi:10.1038/sj.ijo.0802527 Published online 18 May 2004.

In this study researchers measured the sleeping metabolic rate of fifteen obese subjects, male and female, before and after they pursued a 15 week weight loss regimen. The researchers predicted the degree of metabolic slowdown they would find in their subjects after weight loss using formulas derived from a control group of 86 non-obese individuals with a wide range of body weights whose sleeping metabolism had been studied with a whole body calorimeter. The formula they came out with was validated by being compared with the findings of another study by other researchers.

At the start of the study the obese subjects had much higher metabolic rates than the controls. After weight loss, though their final metabolic rate value was within the range for normal people who weighed on average considerably less than they did, the amount by which their metabolic rate had dropped was almost twice what had been predicted. You can view the graph showing the result HERE.

Analysis of the blood of the participants for

fasting plasma leptin, total T3,free T4, and total plasma OC concentrations after weight loss as well as their changes induced by weight loss were used as predicting variables. As the change in plasma OC concentration is associated with the loss of FM [fat mass], and since Dulloo and Jacquet have reported that fat depletion (loss in FM as a %
of initial FM) is a determinant of the adaptive fall in basal metabolic rate during weight loss, fat depletion was correlated with the change in plasma OC concentration. This correlation was significant (r2 >0.37, P0.05), and fat depletion was thus included as the predicting variable in the analysis. As shown in Table 2, the change in total plasma OC concentration was the main factor explaining deviations in SMR from predicted values in response to weight loss (r2¼0.47).

In their summary they restated this more simply:

Increased plasma OC concentration was the factor explaining the greatest proportion of the difference between predicted and measured SMR [sleeping metabolic rate] changes induced by body weight loss. OC [organochlorine] pollution seems to be a new factor affecting the control of thermogenesis in some obese individuals experiencing body weight loss.

So what, you may ask are "organochlorines?"

The answer is a host of organic pollutants that pervade our environment. At the top of the list is vyinyl chloride, an ingredient in PVC plastics. The NIH's Report on Carcinogens (11th ed) describes vinyl choride as a known cause of cancer known to cause genetic damage. It also explains

PVC is a plastic resin used in many consumer and industrial products, including automotive parts and accessories, furniture, medical supplies, containers, wrapping film, battery cell separators, electrical insulation, water distribution systems, flooring, windows, videodiscs, irrigation systems, and credit cards.

But that is only one source of organocholorines. They also found in pesticides, industrial solvents, and the PCBs still found in our environment thanks to decades of industrial use.

The researchers also calculated the impact of the dramatic drop in leptin (expected with weight loss) and concluded that

The main finding of this study was that the changes in plasma OC concentration were the main predictor of adaptive thermogenesis, and explained about 50% of its variance. As discussed above, this is not a surprise since these compounds produce significant alterations of mitochondrial activity and of the thyroid function.

In short, while we expect dieters to experience slowed metabolisms after dieting thanks to some natural changes, a major one of which is the drop in leptin levels, it appears that the presence of these chemical pollutants in our body is causing the metabolic slowdown to be much steeper than predicted.

And from a practical standpoint what this means is that a person whose body is filled with these chemicals who manages to lose weight will have an extremely hard time maintaining that weight loss--harder than would be the case were their bodies not filled with these chemicals that damage their mitchondria (the cell units that burn energy) and their thyroids.

This finding correlates with others we have discussed elsewhere that link incidence of diabetes in various populations with their exposure to PCBS, plastics, and pesticides. These other studies suggest that the organochlorines not only explain why it is so difficult to lose weight, but possibly why people gain weight in the first place, since these chemicals destroy the systems used to control blood sugar, and ravenous hunger is a side effect of poor blood sugar control.

Coincidentally, as I was getting ready to write this blog post I found a new article in Science Daily which linked the high level of liver damage found in Americans exposure to their blood-load of pollutants. That report can be read here:

Environmental Pollution Increases Risk Of Liver Disease, Study Finds

In that report we read:

""Our study found that greater than one in three U.S. adults had liver disease, even after excluding those with traditional risk factors such as alcoholism and viral hepatitis," said Matthew Cave, MD, assistant professor, department of medicine, division of gastroenterology and hepatology at the University of Louisville. "Our study shows that some of these cases may be attributable to environmental pollution, even after adjusting for obesity, which is another major risk factor for liver disease."

Using the 2003-2004 National Health and Nutrition Examination Survey (NHANES), researchers from the University of Louisville study examined chronic low-level exposure to 111 common pollutants including lead, mercury, PCBs and pesticides and their association with otherwise unexplained liver disease in adults. The specific pollutants included were detectable in 60 percent or more of the 4,500 study subjects. [emphasis mine]

You hear a lot about how fat people should be blamed for causing their obesity by indulging in gluttony and sloth. I don't question that people who get fat do so by eating a lot more than they should. But I go further than this. I ask WHY are the inbuilt physiological mechanisms which, in normal people, control appetite and maintain weight at a set point, all of a sudden completely nonfunctional in so many people?

Decades of research show that if you overfeed a normal person, they will quickly return to their normal weight thanks to the existence of a built-in weight set point regulation system. Decades of research also show that normal people have appetite control systems that control their food intake so exquisitely that a normal person will gain only 20-30 lbs over 40 years of life--which means that over a lifetime they are only overeating ten calories a day.

The obesity epidemic is a measure of how damaged our bodies have become and studies like this one--completely ignored by the media--point to why they are damaged.

It isn't moral failure, it's chemical poisoning. I personally believe chemical pollution and its effects on our bodies, worldwide, is a far greater crisis than the energy crisis and one a lot more likely to put human survival into doubt. More and more of our children are being born with conditions reflecting severe genetic damage. More and more people are battling infertility, too.

Personal responsibility is not going to solve this problem. Until we, as a society, demand that corporations stop poisoning our environment and selling us products that damage our bodies, it will only get worse.